Steam rook drill



2 Sheets-Sheet 1.

(No Model.)

W. T. BELL.- STEAM ROCK DRILL.

Patented June 6, 1882.

W. T. BELL.

Patented June 6, '1882,

UNITED STATES PATENT OFFICE.

WILLIAM T. BEL on new YORK, n. Y.

STEAM. ROCK-DRILL.

SPECIFICATION forming part of Letters Patent No. 258, 974, dated June 6, 1 882.

. Application filed February 13, 1882. (No model.)

1'0 all whom it may concern Be it known that I, WILLIAM T. BELL, of the city, county, and State of- N ew York, have invented certain new and useful Improvements in Steam Rock-Drills, which are hereinafter fully and clearly described, reference being made to the annexed drawings, which form apart of this specification.

Myimprovements are applicable especially to rock-drills where rotary and vertical. motions are required at the same time; but my invention may also be. applied successfully to steam-pumps and other steam-cylinders.

The object of. my invention is to dispense with valves and ratchets in rock-drills and the heavy, expensive, and cumbrous machinery necessary to operate them.

In all kinds of rock-drills two concurrent motions of the drill are necessary to effectually produce the desired resultnamely, a rotary and a vertical motion. The vertical motion in rock-drills has heretofore been obtained by an ordinary piston and valves operated by the cylinder-piston. Fig. 2 is a transverse section of the cylinder, piston, and steamways. Fig. 3 is a plan view of the irregular grooves in the upper chamber of the cylinder. Fig. 4 is a plan view of the piston with its steam and exhaustways. Fig.5 is a transverse sectional view of the same. Fig. 6 is a transverse section of the cylinder and the supply and ex-- haust pipes.

On the upper end of the piston A there are constructed and attached two or more studs, 0 0, set opposite each other, and made in the form of an ellipse. These two studs operate in the vertical irregular grooves d d d and a an shown in Figs.4 and 5. As the piston ascends it makes a partial revolution, as above explained,which brings the two uppermost steamways or grooves, g g, directly opposite the holes f f in the steam-cylinder, where the steam is admitted and the piston forced downward, when it makes another partial revolution, which carries these same steamways round directly opposite the holes 8 sin the cylinder, where the steam is exhausted. Again, when the piston is forced downward and makes a partial revolution, as explained,'the grooves g g are brought directly opposite the holes ff in thesteam-cylinder, where the steam is admitted and the piston forced upward to the point where the steam is exhausted, as before explained. Thus it will be seen that valves are entirely dispensed with, and that the piston is constructed and made to operate in such a manner as to form of itself an automatic valve or valves. 1

The piston and cylinder of this rock-drill WILLIAM T. BELL.

e Witnesses:

E. G. DELANEY, G. MGDOUGALL. 

